3 Clinical relevance

Petechiae cannot be pushed away using a glass spatula or a finger. Even under pressure, the reddening of the skin remains visible. This shows that petechiae are caused by extravasated fluid, which differentiates it from different red rashes, e.g. small hemangiomas.

4 Forensic medicine

Periorbital petechiae in the region of the head of a corpse indicate venous obstruction in the course of strangulation. The cause are obstructed veins of the neck, whereas blood flow through the carotid arteries continues.